Bone anchor delivery system device and method

ABSTRACT

A bone anchor delivery system device ( 10 ) has a retractable punch driver assembly and a locking mechanism ( 32 ). The punch driver assembly has a retractable punch shaft ( 30 ) and a guide ( 20 ) for receiving the retractable punch shaft ( 30 ). The guide ( 20 ) is rotatable relative to the punch shaft ( 30 ) and the shaft has an extended length with bone penetrating tip ( 35 ) at a first end ( 33 ). The locking mechanism ( 32 ) for locking the retractable punch shaft ( 30 ) from linear movement and rotational movement relative to the guide ( 20 ) is positioned at an opposite second end. The retractable punch shaft ( 30 ) has a reduced diameter end ( 33 ) extending from the tip ( 35 ) toward a shoulder stop for receiving a releasable punch ( 12 ). The releasable punch ( 12 ) has a hollow opening for receiving the reduced diameter end ( 33 ) of the punch shaft ( 30 ). The punch ( 12 ) is profiled to pierce and form a bone anchor hole.

RELATED APPLICATIONS

The present application is a continuation of co-pending U.S. applicationSer. No. 14/527,043 filed Oct. 29, 2014 entitled “Bone Anchor DeliverySystem Device And Method”.

TECHNICAL FIELD

The present invention relates to methods and instruments for fixation ofsutures and tissue to bone, more particularly to a bone anchor systemfor securing sutures for attachment of soft tissue like ligament andcartilage to bone.

BACKGROUND OF THE INVENTION

The use of bone screw anchors to hold sutures is a widely acceptedpractice in shoulder or knee repair and fixation of soft tissue such asligaments, cartilage and tendons to bone. Ideally the suture anchor iseasy to install and provides a solid reliable way to fix the sutures tothe bone. The bone has a hard outer cortical shell with a softerunderlying region of cancellous bone tissue. The anchor must holdsutures after thousands of repetitive motions tensioning and relaxationuntil the ligament or tendon repair has time to heal and secure itselfto the bone and muscle tissue.

Older style bone anchors had an external eyelet to allow the sutures tobe fed through after the screw was driven into the bone. This left theeyelet exposed in the soft muscle tissue.

Later versions of bone anchors have the sutures inserted inside thescrew tip well inside the bone. This allows the screw outer end to stayflush with the cortical bone outer surface. The sutures can pass insidein some hollow screws from the tip to the outer surface. Others have thesutures held at the tip end and are exterior held between the anchorscrew threads and the bone. In some suture anchor systems there is aself-driving feature that has a stainless steel punch with a steel tipthat can be malleted into the bone. This design leaves the tip endtrapped in the bone opening meaning the patient has a small steel tip inhis shoulder or knee.

Ideally the procedure should insure the bone anchor is easily installedleaving no punch tip fragments in the body and more particularlyavoiding having steel tips or metal fragments left in the bone.

The present invention provides a threaded bone anchor that is easy toinstall wherein the sutures are held without leaving metal fragments ormetal tips and, furthermore, this is accomplished with a uniqueinsertion tool and anchor screw assembly to make the procedure simpleand convenient to use.

SUMMARY OF THE INVENTION

A bone anchor delivery system device has a retractable punch driverassembly and a locking mechanism. The punch driver assembly has aretractable punch shaft and a guide for receiving the retractable punchshaft. The guide is rotatable relative to the punch shaft and the shafthas an extended length with bone penetrating tip at a first end. Thelocking mechanism for locking the retractable punch shaft from linearmovement and rotational movement relative to the guide is positioned atan opposite second end. The retractable punch shaft has a reduceddiameter end extending from the tip toward a shoulder stop for receivinga releasable punch. The releasable punch has a hollow opening forreceiving the reduced diameter end and bone penetration tip at the firstend. The punch is profiled at a first end to be complimentary to the tipto pierce and form a bone anchor hole and has an opposite second end forabutting the shoulder of the punch shaft.

Preferably, the reduced diameter end of the punch shaft and the punchhave a snap lock feature to hold the punch. The snap lock feature allowsfor rotational movement of the punch relative to the punch shaft. Thereleasable punch has a plurality of openings for threading one or moresutures. In one embodiment, the releasable punch openings are one ormore pairs of slots sized to receive a plurality of sutures.

The bone anchor delivery system device further has a releasable threadedbone anchor. The threaded bone anchor is hollow having an openingattachment onto the guide. The bone anchor extends from a first leadingend to an opposite second end abutting the guide. The guide has areduced end having a releasable snap locking feature and the bone anchorhas a complimentary releasable lock for holding the bone anchor to theguide. The bone anchor delivery system device has the punch shaftextending past the guide to the shoulder second end by a length L,wherein L is equal to the length of the bone anchor. In the use of theanchor delivery system device, the punch end tip penetrates the bonecreating an opening or hole extending to a depth wherein the bone anchoris positioned adjacent above the bone opening and thereafter threadedinto the bone opening or hole.

The bone anchor delivery system device further has a handle assembly.The handle assembly has a lower portion rotatable about the guide and anupper portion fixed to the guide and wherein the upper portion isrotatable independent of said lower portion. The upper portion has animpact end for impacting the handle assembly to drive the punch throughbone using a mallet if needed. The upper handle has a slot to receivethe locking mechanism to prevent linear movement of the retractablepunch shaft. The punch shaft is a rod or wire and the locking mechanismis integrally formed as part of the rod or wire at a second distal endby a bending of the punch shaft to form a spring like lock snap end tofit into the upper handle slot locking the punch shaft in place. Thespring like snap end when released from the slot allows the punch shaftto move linearly in an elongated slotted opening in the upper handle toretract the punch shaft. Rotation of the upper handle after the lockmechanism is released allows the bone anchor to be driven into said boneopening formed by the punch. The punch is released from the punch shaftend by withdrawing of the punch shaft end and the abutting the end ofthe driven bone anchor. The release of the initial retractable punchassembly occurs by pulling past the snap feature in the guide and thebone anchor. The lower handle provides a non-rotatable hand grip forstabilizing the device as the upper handle is rotated. Preferably, thepunch and the bone anchor are non-metal. The bone anchor or the punchcan be made of synthetic or natural non-metal material. Either can bemade of a plastic material, the plastic material is preferably PEEK. Thepunch or bone anchor also can be made of a bioabsorbable material. Thebone anchor can be made of cortical bone.

DEFINITIONS

As used in this specification, the singular forms “a,” “an” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, the term “a material” is intended to mean one or morematerials, or a combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described by way of example and with reference tothe accompanying drawings in which:

FIG. 1 shows a perspective view of the bone anchor delivery systemdevice of the present invention.

FIG. 2A is a first side plan view of the device of FIG. 1.

FIG. 2B is a second side plan view of the device in FIG. 2A rotated 90degrees.

FIG. 2C is a third side plan view of the device of FIG. 2A rotated anadditional 90 degrees.

FIG. 2D is an end view of the device of FIG. 1.

FIG. 2E is a cross sectional view of the device taken along lines 2E-2Eof FIG. 2B.

FIG. 2F is an enlarged side view showing a portion of the device.

FIG. 3A is an enlarged side view of the leading end portion of thedevice taken from FIG. 2B.

FIG. 3B is a cross sectional view of the leading end portion of thedevice taken along lines 3B-3B of FIG. 3A.

FIG. 4A is an enlarged view of the releasable snap retention feature ofthe threaded bone anchor and the guide taken from FIG. 3B.

FIG. 4B is an enlarged view of the punch shaft tip releasable snapretention feature taken from FIG. 4A.

FIGS. 5A-5D illustrate the method of using the device to install thebone anchor of the present invention with sutures.

FIG. 5A shows the step of locating the insertion position.

FIG. 5B shows the step of driving the punch to depth.

FIG. 5C shows the steps of releasing the lock mechanism and driving theanchor by rotation of the device until flush with the bone surface.

FIG. 5D shows the step of pulling back the device to release it from thebone anchor.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, a perspective view of a bone anchor deliverysystem device 10 is illustrated. As further shown in FIGS. 2A-2D, thedevice 10, as illustrated, has a two part handle 40, a lower handle 42which is rotatable about a guide 20 and an upper handle 44 which isfixed to the guide 20. As further illustrated in FIG. 1, the guide 20extends from the handle 40 located at a second end to a leading firstend. The guide 20, as illustrated, is hollow and has a punch shaft 30extending from inside the guide 20 to the leading first end. At the verytip 35 of the leading first end 33 of the guide 20 is illustrated areleasable punch 12. Extending further up the punch shaft 30 isillustrated a bone anchor 14. The bone anchor 14 preferably has a lengththat is approximately equal to the length of that part of the shaft 30extending beyond the guide 20, as illustrated. The bone anchor 14preferably is a threaded screw structure hollow on the inside whichallows the punch shaft 30 to extend through the bone anchor 14, asillustrated. At the handle end 40, the guide 20 is shown extendingpartially into a slotted opening 41 of the upper handle 44 asillustrated in FIG. 2B. The punch shaft 30 extends beyond the guide 20and is bent and wrapped around the handle 44 as illustrated. This punchshaft 30 extends from the slot 41 upwardly and at the bend is wrappedaround the upper handle 44. This bend forms a spring like stop mechanism32 that fits into slots 43 and 45 in the handle 44. This prevents thepunch shaft 30 from moving linearly or rotating relative to the device10. As further shown, the upper handle portion 44 has a rounded somewhatflattened head or end 46. This flattened end 46 is adjacent a grooveportion above the upper handle 44. This end 46 provides a surface onwhich a surgeon may take a mallet and drive the device into bone.

The punch shaft 30 is best illustrated in the cross sectional view FIG.2E wherein the punch shaft 30 is shown bent into the configurationmaking the spring type tension locking mechanism 32 that is easilysnapped into position into the upper handle 44 as illustrated in FIG.2E. To release the punch shaft 30 from the slots 43 and 45 holdinglocking mechanism 32, the surgeon simply pushes on the folded over end34 as illustrated in FIG. 2E which will release the tension on thespring lock mechanism 32 and allow the punch shaft 30 to rotate backinto the slot opening 41, when this occurs the punch shaft 30 is free tomove linearly up or down relative to the guide 20.

With reference to FIGS. 3A, 3B, 4A and 4B, the leading end of theretractable punch driver assembly is illustrated. The retractable punchdriver assembly comprises the guide 20 which is a hollow cylindricaltube into which the punch shaft 30 fits and extends from the lockingmechanism 32 through the guide 20 and extends beyond the guide by adistance L. This distance L preferably extends sufficiently that thethreaded bone anchor 14 fitted over an end 22 of the guide 20 asillustrated occupies approximately the same distance L between the endof the punch 12 and the guide 20. By providing the threaded bone anchor14 of a length approximately equal to this extension of the punch shaft30, it is possible to drive the punch 12 into the bone and leave thethreaded bone anchor 14 above the bone surface. This enables the boneanchor 14 to be then rotationally driven into the bone opening createdby the punch 12 once the device 10 has punched an opening into the bone.As shown in FIG. 3A, the punch 12 has a plurality of openings 11 toaccept or receive sutures (not illustrated). As shown, these openings 11can be slots to accommodate several sutures if so desired, preferablythe sutures are threaded into and extend from one slot 11 inside thepunch 12 through the other slot 11 to create a fixation of the suturewithin the punch 12, the ends of the suture being outside the device 10.

With reference to FIG. 3B, it is important to look at the punch 12 as ithas a hollow opening for receiving the reduced diameter leading end 33of the punch shaft 30. The end 33 of the punch shaft 30 is sharpened toa point at the tip 35 as illustrated. This reduced diameter end 33preferably has a small ring 37 located between a shoulder 39 of thelarger diameter portion 31 of the punch shaft 30 and the tip 35. Thisring 37 as illustrated in FIG. 4B creates a snap locking feature. Thepunch 12 has a complimentary groove 13 that fits into the snap lockingfeature ring 37. As shown the punch 12 extends up to and abuts thelarger diameter portion 31 of the punch shaft 30. On assembly, the snapfeature ring 37 receives a groove 13 in the punch 12. Alternatively, agroove could be provided in the end 33 of the punch shaft 30 and aprotrusion provided in the punch 12; however it is believed strongerthat the punch 12 be provided with the groove 13 and the end 33 have aprotrusion ring 37 on it. As illustrated, this ring 37 in connectionwith the groove 13 creates a releasable snap lock feature that enablesthe punch 12 to be placed over the tip 35 and end 33 snapped intoposition and held there. This prevents the punch 12 from slipping offinadvertently and is important that it be easily releasable once thepunch 12 has been driven into the bone with the sutures in place in theslotted openings 11, as will be discussed later.

With reference to FIGS. 3B and 4A, the guide 20 extending over the punchshaft 30 has a one or more flat surfaces 22 at a leading or first end ofthe guide 20 and the bone anchor 14 similarly has one or more flatsurfaces 16 complimentary to fit in a non-rotational fashion such thatthe bone anchor 14 is secured directly to the guide 20, preferably theguide 20 can be machined to a square and the anchor will have a squareopening. The guide 20 further has a snap lock feature 27 at a reduceddiameter end of the guide 20. This snap feature is a ring 27 similar tothe snap feature 37 provided on the punch 12 and provides a protrusionor ring 27 around the reduced diameter portion 23 of the guide 20 thatenables the bone anchor 14 to snap onto and be held there so that it isretained in this position as an assembly. This retention is releasablewith a small amount of pressure enabling the bone anchor 14 to bereleased from the device 10 upon insertion into the bone. As shown, thebone anchor 14 preferably uses double helix tapered threads 15 that aresufficiently large to allow the bone anchor 14 to enter into the openingcreated by the punch 12 and to aggressively hold the anchor 14 intoposition in the cortical bone. It is important to note that the punchshaft 30 has an extended fixed distance that allows for punching thepunch 12 a controlled depth leaving a length equal to the length L ofthe anchor 14. As discussed, it is important that the extension extendbeyond the leading end of the bone anchor 14 by a distance at leastequal to the total length of the bone anchor itself. Preferably, the tip35 of the punch shaft 30 and the entire punch shaft 30 is made ofstainless steel. The sharpened tip 35 assists in penetrating the bonealong with the punch 12. It is preferable that the punch 12 and the boneanchor 14 be made of non-metal. Alternatively, while the anchor 14 andpunch 12 could be made of metal, but it has been found that leavingremnants of metal in bone is not a preferred practice, and therefore, itis believed that a synthetic material such as plastic, preferablypolyether ether ketone (PEEK) and or a bioabsorbable material would bepreferred. The threaded bone anchor 14 itself may even include abioabsorbable or natural material such as cortical bone. These and otherpossible materials are easily used in the manufacture of this device 10.It is even possible that natural compositions can be molded or cementedtogether in such a fashion that the punch itself can be made of anatural composition with the assistance of certain cements that wouldenable the punch 12 to be absorbed readily into the body, if so desired.

As shown, the punch 12 has a complimentary leading end that matches tothe sharpened tip 35 of the end 33 such that upon hole penetration, theentire punch 12 has a diameter sufficient that it will allow the leadingedge of the bone anchor 14 to engage the opening to initiate threadinginto the hole to secure the bone anchor 14 into the hole created by thepunch 12.

To better understand how the invention is used, reference is made toFIGS. 5A-5D. It is important to note that the surgeon should locate theposition in which he wants the bone anchor 14 inserted. The bone anchor14 with sutures 50 passed through slots 11 of the punch 12 will bepositioned on the delivery device 10 and oriented in the desireddirection the punch 12 is to penetrate into the bone 2. Once thisposition is secured, the surgeon can push and or use a mallet to punchto the desired depth. As shown in FIG. 5B, when the punch 12 achievesthe desired depth, the anchor 14 is positioned directly above theopening at the outer surface of the cortical bone 2. The sutures 50 willbe extending along the sides of the anchor 14, as illustrated. Thesutures 50 can preferably be held off to one side or the other as theyare retained in the punch 12 at the bottom of the hole 3 just created.The surgeon can then release the lock mechanism 32 of the punch shaft 30and rotate the upper handle 44 of the device 10 such that the boneanchor 14 can be threadingly engaged and driven into the opening 3 incortical bone 2 and cancellous bone 4 until it is flush with the surfaceof the cortical bone 2. As the surgeon is rotating the device 10, thetwo part handle 40 provides an optimal way for the surgeon to hold thelower handle 42 stationary as it free to rotate relative to the rotationof the guide 20 and the upper handle 44. The upper handle 44 being fixedto the guide 20 allows the lower handle 42 to be held in thenon-rotatable fashion as the surgeon rotates the upper handle 44 therebydriving the bone anchor 14 into the bone 4. As the bone anchor 14 isbeing driven into the bone 4, the punch shaft 30, being released fromthe locked position, is free to linearly move outwardly relative to thebone opening. During this movement, the punch 12 can be released at anytime. The snap release feature 37 is easily overcome by the resistanceof the bone tissue 4. Alternatively, the punch 12 could, if the tissue 4is very soft, continue to ride up the punch shaft 30 as it moves outwardduring the rotation and the driving of the bone anchor 14, such that,when the punch bottoms against the bone anchor 14, it will automaticallyrelease from the shaft 30. Once the bone anchor 14 is flush at the bonesurface the surgeon simply pulls back and the snap release feature 27 onthe guide holding the bone anchor 14 will similarly release allowing theentire device 10 to be pulled free. The beauty of this inventive device10 is that the entire drive assembly is pulled free of the punch 12 andanchor 14 in such a fashion that no remnants of the punch driverassembly are left in the body. In this way, when the bone anchor 14 andpunch 12 are made of non-metallic material, it is possible that the boneanchor 14 and punch 12 can be delivered in a relatively simplestraightforward way wherein the entire drive device 10 excepting thepunch 12 and anchor 14 is pulled out free of the patient leaving nometallic materials in the patient.

In almost all other conventional bone anchor delivery systems, thesurgeon is required to hold a handle and rotate the device and theentire device rotates as the bone anchor is being positioned into thebone. When this occurs, the surgeon has no ability to either stabilizethe device as provided in the present invention and further by beinggloved, the surgical gloves have a tendency to wrap about the rotatingprior art devices as they are being rotated, if the surgeon isattempting to hold onto the device with his other hand as he is rotatingthe device to anchor a bone anchor.

With the present invention, the gloved hand of the surgeon is held on anon-rotating lower handle portion 42 of the two part handle 40 as theupper handle portion 44 of the handle 40 is rotated, thereby driving thebone anchor 14. While this is a simple innovation, it is believedsignificant in that the surgeon can stabilize the bone anchor 14preventing it from wobbling using two hands; one hand strictly forstabilization as the other hand provides rotation. More importantly, itis designed so that the surgeon's glove does not get wrapped orotherwise pinched into the rotating portions of the device. No otherprior art device is known to have such a feature.

Furthermore, to the unique simplicity of the device 10 wherein the punchshaft 30 is made basically of a single stainless steel wire that has amachined leading end 33 sharpened to a point at the tip 35 of thereduced diameter and extends upwardly to an end where the wire is bentand formed to form a locking mechanism 32 that locks into slots 43, 45in the upper handle 44. This locking feature being integral to the wiremakes it a very low cost structure. Fundamentally, the device 10 is madeof a guide 20, a punch shaft 30 and two handle portions 42, 44. Thehandle portions are plastic molded parts. This provides for a reasonablylow cost, if not very low cost, bone anchor delivery system. The boneanchors 14 themselves can be small plastic components as well. Thismeans that the surgeon will be able to use this device and throw it awayif so desired due to its significant simplicity and low costconstruction.

Variations in the present invention are possible in light of thedescription of it provided herein. While certain representativeembodiments and details have been shown for the purpose of illustratingthe subject invention, it will be apparent to those skilled in this artthat various changes and modifications can be made therein withoutdeparting from the scope of the subject invention. It is, therefore, tobe understood that changes can be made in the particular embodimentsdescribed, which will be within the full intended scope of the inventionas defined by the following appended claims.

What is claimed is:
 1. A bone anchor delivery system device comprising:a retractable punch driver assembly, the punch driver assembly having aretractable punch shaft and a guide for receiving the retractable punchshaft, the guide being rotatable relative to the punch shaft and theshaft having an extended length with bone penetrating tip at a firstend; and a locking mechanism for locking the retractable punch shaftfrom linear movement and rotational movement relative to the guide at anopposite second end; a handle assembly, the handle assembly having alower portion rotatable about the guide and an upper portion fixed tothe guide and wherein the upper portion is rotatable independent of saidlower portion, the upper portion has a slot to receive the lockingmechanism to prevent linear movement of the retractable punch shaft; andwherein the punch shaft is a rod or wire and the locking mechanism isintegrally formed as part of the rod or wire at a second distal end by abending of the punch shaft to form a spring like lock snap end to fitinto the slot of the upper portion locking the punch shaft in place. 2.The bone anchor delivery system device of claim 1 wherein theretractable punch shaft has a reduced diameter end extending from thetip toward a shoulder stop for receiving a releasable punch, thereleasable punch having a hollow opening for receiving the reduceddiameter end and bone penetration tip at the first end profiled to becomplimentary to the tip and an opposite second end for abutting theshoulder stop of the punch shaft.
 3. The bone anchor delivery systemdevice of claim 2 wherein the reduced diameter end of the punch shaftand the punch have a snap lock feature to hold the punch, the snap lockfeature allows for rotational movement of the punch relative to thepunch shaft.
 4. The bone anchor delivery system device of claim 1wherein the releasable punch has a plurality of openings for threadingone or more sutures.
 5. The bone anchor delivery system device of claim4 wherein the releasable punch openings are one or more pairs of slotssized to receive a plurality of sutures.
 6. The bone anchor deliverysystem device of claim 3 further comprises a releasable threaded boneanchor, the threaded bone anchor being hollow having an opening forattachment onto the guide, the bone anchor extending from a firstleading end to an opposite second end abutting the guide.
 7. The boneanchor delivery system device of claim 6 wherein the guide has a reducedend having a snap lock feature and the bone anchor has a complimentaryreleasable lock for holding the bone anchor to the guide.
 8. The boneanchor delivery system device of claim 7 wherein rotation of the upperportion after the lock mechanism is released allows the bone anchor tobe driven into a bone opening formed by the punch.
 9. The bone anchordelivery system device of claim 8 wherein the punch is released from thepunch shaft end by withdrawing of the punch shaft and abutting theleading end of the driven bone anchor.
 10. The bone anchor deliverysystem device of claim 9 wherein the release of the initial retractablepunch assembly occurs by pulling past the snap lock feature in the guideand the bone anchor.
 11. The bone anchor delivery system device of claim8 wherein the lower portion provides a non-rotatable hand grip forstabilizing the device as the upper portion is rotated.
 12. The boneanchor delivery system device of claim 6 wherein the punch shaft extendspast the guide and the leading end of the bone anchor when the boneanchor is attached and abutted to the guide at the second end by alength L, wherein L is at least equal to the length of the bone anchorand wherein in the use of the anchor delivery system device the punchtip penetrates the bone creating an opening extending to a depth whereinthe bone anchor is positioned adjacent above the bone opening.
 13. Thebone anchor delivery system device of claim 1 wherein said upper portionhas an impact end for impacting the handle assembly to drive the punchthrough bone.
 14. The bone anchor delivery system device of claim 1wherein the spring like lock snap end when released from the slot of theupper portion allows the punch shaft to move linearly in an elongatedslotted opening in the upper portion to retract the punch shaft.
 15. Thebone anchor delivery system device of claim 2 wherein the punch isnon-metal.
 16. The bone anchor delivery system device of claim 2 whereinthe punch is made of synthetic or natural non-metal material.
 17. Thebone anchor delivery system device of claim 2 wherein the punch is madeof a plastic material.
 18. The bone anchor delivery system device ofclaim 17 wherein the plastic material is PEEK (polyether ether ketone).19. The bone anchor delivery system device of claim 2 wherein the punchis made of a bioabsorbable material.
 20. The bone anchor delivery systemdevice of claim 2 wherein the anchor is made of a hardened biologicalmaterial composition.
 21. The bone anchor delivery system device ofclaim 2 wherein the bone anchor is non-metal.
 22. The bone anchordelivery system device of claim 2 wherein the bone anchor is made ofsynthetic or natural non-metal material.
 23. The bone anchor deliverysystem device of claim 2 wherein the bone anchor is made of a plasticmaterial.
 24. The bone anchor delivery system device of claim 2 whereinthe bone anchor is made of a bioabsorbable material.
 25. The bone anchordelivery system device of claim 2 wherein the bone anchor is made ofcortical bone.